<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <link rel="stylesheet" href="style.css">
    <title></title>
  </head>
  <body>
    <div class="box">
      <div class="b b1"></div>
      <div class="b b2"></div>
      <div class="b b3"></div>
      <div class="b b4"></div>
    </div>
  </body>
</html>
